Steam boiler



llryl-llUNITED srATEs rA'reNrorrlcs.:

EDGAR KIDWELI., OMIIILWAUKEE, WISCONSIN, AssIGNoR To KIDWELL BoILER COM- l PANY, or MILWAUKEE, WISCONSIN, A conronArIoN-jnpIscoNsIN.

Application led December 4, 1923. Serial No. 678,409.

To all whom 'it may cmwem."

Be it lmown that I, EDGAR KIDwnLL, a citizen of theUnited States, and resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented .certain new and -useful Improvements in Steam Boilers, of which the following is a speciication.

This invention relates to water-tube boilers wherein are employed two or more upper steam-and-water drums .connected by overcomer orsuperheater tubes in such a manner that the steam which is liberated from the water contained in the water space of one or more drums is delivered tothe steam space of another drum.

An object of my invention is to construed@Y la boiler having provisions whereby @egimpurities contained in the moisture that 'is' carried over by the liberated steam are efried over thereby, .which impurities arev thence deflected to the water contained in the drum and precipitated therein such a manner that the deposit canlb-e `readily withdrawn by means of ablow-oif connection in the bottom of vthe drum. g The purilied steam is caused to pass from the drum n to and through a. series of secondary super-A heating tubes leading to a suitable header from which the steam is finally delivered for service. Such superheating tubes are positioned directly beneath and longitudinally of the primary superheating tubes so' as to be subjected to the efficient action of the furnace gases in theirupward, rearward and downward flow through the boiler structure; all as hereinafter fully described and claimed.

Referring to the drawing, which repre- A sents a longitudinal vertical section of the upper portion of one type ofwater-tube boiler containin two steam-and-water drums and emb ying my invention. 2, 3

designate two upper steam-and-water drums, whereof the former constitutes a rear steamdisengaging element which 'is included in the main path of water circulation, and whereof the latter drum 8 constitutes a front steam-receiving element remote from such circulation path. The steam spaces of the respective drums are connected by superheater tubes` or overcomers 4, and the water spaces ofthe respective drums are connected by means of opposite-How tubes 5 which function toestablish a supplementary water circulation between the two drums and maintain therein a uniform water level, as more fully described in Letters Patent of the United States No.v 1,442,- llrdated January 16, 1923, to which refer- The lsteamgggvhich is liberated from the circulating boiler water in the drum -2 flows through the 'overcomer tubes 4 into the steam space of the drum 3, such steam in its passage through the tubes 4 being subjected to a gas temperature outside'ofthe tube sufiiciently high to superheat the steam. The steam upon entering the overcomer tub'es 80 carries with it a certain percentage of moisture which is in consequence. of the superheat evaporated in its passage through the` tubes, and in-consequence any impuritiesv that are held in solution or in suspension in the' entrained moisture are left as a residue from the evaporation and fall, as an impal' pable dust, to the bottom of thetubes, which dust is, perforce, swept onward by the steam intorthe form@ drum. In the absence of no separating meansd when thesteam in sat1- urated orwet condition is drawn directly from the v,boiler nozzley-all impurities contained in it are drawn Vinto the steam outlet pipe from the drum 3, resulting in much trouble, such, for example, as the erosion of the primev movers, the scoring of the-,engine cylinders and valves, and the cloggingA of steam-flow leads and traps. A

Engineers have only recently realized what a great percentageas high as 90%- of the total impurities in the water is swept out into the steam pipe by VVwet steam,Y The serious consequences of allowing such a volume of impurities to go out with'the steam 105 can be realized from the fact that it has been found insome plants that the amount of sediment blown out through the pipe 7, in

`my invention as below described,is double the amount blown out through the bottom blow-oil' valves of the boiler.

In pursuance oi: my invention Iarrange within the drum 3, above the surface of the water contained therein, a baille 6 upon which the incoming steam and dust impinge at an acute angle, which steam is thus deflected forward and prevented from striking the water contained in the drum, While the dust is swept oil' the baille and precipitated into the water. This dust, becoming saturated, settles to the bottom of the .water in the drum and forms a sediment or sludge that can be readily removed by and through the blow-oil' pipe 7 extending 'from the bottom of the drum.

In order to subject the purified steam toV a high degree otsuperheat before the d1s charge ot the steam from the boiler, I connectthe steam space of the drum 3 by means of a series .of steam flow leads S with a header 9 which is illustrated as arranged above and longitudinallyof thesaid drum. These leads are entered into the drum in a plane above the baille G, andthcy are located within the space directly beneath and longitudinally ot the overcomers l kin such .manner that the 'furnace gases in their upward, rearward and downward passage from the furnace chamber to the stack, flow amongst and effectively heatthe leads 8, such leads thus constituting a steam superheatcr. Since the impurities are eliminated from the steam before it has an opportunity to enter the superheater, the walls of the later do not become encrusted with secretions and thus overheated, and therefore the imacat -steamvandnvater drums whereotl one con 'stitutes asteanrdlsengagmg element 1ncluded inthe main path ot' water circulation, and another drum constitutes a steamreceiving element remote from said path,

f and having also opposite-dow tubes connecting the water spaces ot the d'rums, and 4overcoiner tubes between the steam spaces ol the respective drums, a baille member arranged within the steam-receiving element at an angle to the delivery path of the overcomer tubes, a steam-receiving header, steamtl0W leads connecting the steani-1eceivi1ig element to the header, said' leads extending directly below and longitudinally of the over-comer tubes to constitute a superheater, and a blowoil pipe for the bottom of the steam-receiv ing element.

2. In a water-tube boiler having upper steam-and-water. drums whereof one constitutes a` steam-'disengaging element included in the main path of water circulation, and the other drum constitutes a steam-receiving element remote from said path, and having also opposite flow tubes connecting the water spaces of the drums, and overcomer tubes between the steam spaces of the respective drums, a steam-receptacle, and 4a series of U-shaped superheater tubes located within the space below and longitudinally of the overcomer tubes and connected at,

their respective ends with the steam-receiv-" ing element and the said receptacle.

Signed at Milwaukee, in the county 'of Milwaukee and State of Wisconsin, this 30th day of November, A. D. 1923.

EDGAR KIDWELL. 

